| A | B |
|---|
| Point | A specific location or mark usually identified by a letter |
| Line | An endless straight path with no endpoints |
| Line Segment | Part of a line between two endpoints |
| Ray | A part of a line that has one endpoint and goes on forever in one direction |
| Plane | An endless flat surface that uses three nonlinear points for its name |
| Vertex | The point where two rays meet, creating an angle |
| Acute Angle | An angle that measures less than ninety degrees |
| Right Angle | An angle that measures exactly ninety degrees |
| Obtuse Angle | An angle that measures greater than 90 degrees but less than 180 degrees |
| Protractor | The semicircular instrument used to measure and/or construct an angle |
| Polygon | A two-dimensional shape that has three or more sides |
| Intersecting lines | Any lines that meet at a point. They do not have to form a ninety-degree angle |
| Parallel lines | Two lines that are an equal distance apart which will never meet |
| Perpendicular lines | Two lines that meet to form a right angle |
| Compass | An instrument that can be used to construct a circle |
